Coupling device for signal transmission and receiving systems



June 11, 1940. CQQLEY r 2,204,529 COUPLING DEVICE FOR SIGNAL TRANSMISSION AND RECEIVING SYSTEMS Filed Aug. 25, 1938 2 Sheets-Sheet 1' INVENTOR ATTORNEY June .11, 1940. A CQQLEY 2,204,529

COUPLING DEVICE FOR SIGNAL TRANSMISSION AND RECEIVING SYSTEMS Filed Aug. 25, 1938 2 Sheets-Sheet 2 f R I V g N INVENTOR ATTORNEY Patented June 11, g

' UNITED. STATES PATENT QFFI'E COUPLING DEVICE SIGNAL TRANS- iiflSSION AND RECEIVING SYSTEMS Austin G. Cooley, New York, N. Y., assignor to Wide World Photos, Inc., New York, N. Y., a,v corporation 01' New York Application August 25, 1938. Serial No. 226,697

5 Claims. (C'l. 119-2) This invention relates to electric communica Fig. 2 is a side elevational view of Fig. 2, partly tion systems andmore especially to systems of in section. commlmication over telephone lines and the like. Figs. 3, 4, 5, 6 and '1 are detail views of parts-of A principal object of the invention is to provide the coupling device of Figs. 1 and 2.

6 an improved apparatus for impressing signals on Fig. 8 is a bottom plan view offFig. 1. l

a telephone line without conductive connection Fig. 9 is a schematic composite apparatus and thereto. circuit diagram to illustrate one application of Another object is to provide a device for couthe invention. pling a signal transmitter or a signal receiver Re e g m e pa a y to Figs- 1 end l0 electromagnetically to the ear-piece of anywellthe'coupling device according to the. invention 10 known form of telephone subscriber's set. p es a ba e P ly, alth g 110i? A feature of the invention relates to a coupling necessarily of aluminum, hard rubber or other device of the type referred to whereby electrosuitable material. Base l is provided with a sema'gnetic coupling of transmitting and receiving ries of channels 2 extending therethrough ,for

1 apparatus "may bemade to existing and welipurposes to be described. The central part of I known telephone terminal equipment without base I is shaped to f a circular recess 3 to requiring any fastening of the device to the teleceive and enclose the electromagnetic system of phone apparatus. the coupling device. The electromagnetic system Another feature relates to a simple, eflicient comprises a core or pile-up of U-shaped laminaand readily assembled coupling unit for electrotions 4 which are clamped toge her et'thel I W- Ii magneticallycoupling signalling transmitting and er ends by a brass member 5 (Fig. 4) the laminareceiving apparatus to the ear-piece of any welltime bei g Sp from the member by fibre known form of telephone talking set. insulator strips 6 of the same shape and size as A further feature relates to an improved electhe laminations. The electromagnetic system tromagnetic coupling device of the type referred also includes a pair of c ils 0r windings I, 8, each 88 to whereby it may be easily placed on a table or coil eing positioned on a co espo d egot other support and whereby the ear-piece of a the laminated core 4 and in order to insulate the telephone talking set can be readilyplaced therewindings from the member 5 there is interposed on without fastening thereto, the coupling device .a fibre or other insulating washer 9 (Fig. 7). The

being provided with a housing to permit incomcore and windings are enclosed in a cylindrical so me signals to be heard without disturbing the brass member ID havine 81011 ll allow the ear-piece. J lead-in wires I! to pass, it being understood of Another feature relates to the novel organizacourse that the wires I! are provided with a suittion, arrangement and relative location of parts able insulating sheath or covering II. If desired 3-5 which constitute an improved form of electrothe winding 01 0011s 1 a seen be connected in 85 magneti coupling and listeningdddevice. series or parallel with the wires l2. The u per Other features and advantages not specifically end of housing member IO is provided with a enumerated will be apparent afteraconsideration tightly fitted brass cover ll (Fig. 6) having a of the following detailed description and the appair of slots IS, it, through which the legs of o J pended claims. While the invention will be disthe core pass. However, it is preferable to slit 0 closed herein in connection with a system of the portion of member ll between the slots I5, I transmitting pictures -or facsimiles over a telel6, as indicated y the numeral It Will be phone line, it will be understood that the device derstood of u se t t cells 8. ar w und according to the invention is capable of being with insulated wire on suitable forms of insulaused with any kind of signal; generator or reprotion material as is wellknown in the art, the 45 ducer. Furthermore, inasmuch as signal generforms being such as to allow them to he slipped ators and reproducers of many types are wellover the legs 01 the core If desired. the 0.011 known in the art this part of the disclosure beforms may be tightly fit d on th re less r ing addressed to those familiar with the art, is separate fastening m ans y be mployed.

illustrated in diagrammatic form. Accordingly After assembly of the core and windings in the IQ inthe drawings: housing the latter may be filled with pitch or- Fig. 1 is a vertical elevational view, partly in other suitable insulating material which upon section showing. the coupling device according to hardening retains the core and windin n fi e the invention in conjunction with a conventional relation. 1

as. telephone ear-piece. a The upper ends ofthe core. laminations are Ii 'coils i, 8, to the coils 2t.

compressed together by a plug it (Fig. 3) of hard rubber or other non-magnetic material which fits tightly over the ends of the laminations. If desired the upwardly projecting ends oi the core legs may be curved to corr spend with the curvature of member M as sho n in Fig. 3. For the purpose of fastening the electromagnetic system in place there is provided a brass ring l9 having a central circular opening into which the member i9 is fitted. Ring is also has a series of smaller openings 20 equal in number to and arranged to be aligned with the channels 2. Ring 19 is fastened in place against the base shoulder it by suitable screws or rivets 22. Preferably the member i0 is a press fit within the recess s so that once it is forced into place it is firmly held in place together with brazed elements 4 to 9.

The base i is provided with an annular rim 2% to which is fastened an annular sound deadening ring 26 of felt or similar material. support the base in a sound deadening relation to a table or other support, it is provided with three or more soft rubber' pedestals 25 fastened by screws 25. The members 25 also serve to space the base i away from the table so as to allow sound waves from the telephone ear-piece or receiver 21 to pass downwardly through the openings 20 and channels 2. By this means it is possible to listen in on received signals as reproduced by the telephone receiver, at the same time that signals are being transmitted by electromagnetic induction from the wins '8,

piece cover to project below the rim 23. By this arrangement it is merely necessary in using the device to remove the ear-piece from the telephone switch-hook and place it as shown in Fig. 1 and the windings '28 will be automatically aligned with the windin s l, 8. It is not necessary to fasten the ear-piece to the base i and.

consequently the ear-piece can be turned at any time while it is resting on rim 23 to get the best transfer of electromagnetic energy from the It will be understood that washers '24 of difierent thickness may be employed in order to achieve the desiredspacing between the core 4 and the diaphragm 8!! of the telephone ear-piece. Likewise if desired, the rim 23 instead of being integral with base i may be threaded on to base I so as to be able to adjust the spacing between the core 4 and the diaphragm 3|. If desired, suitable marks (63, 56,- Fig. 9) can be provided on the ear-piece and on the member I which when in alignment indicate that the magnetic poles of the ear-piece are in gqlignment with the ends of core 4 as shown in 2. Referring to Fig. 9, there is shown in block diagrammatic form, a typical signalling system embodying the. coupling arrangement shown in Figs...lto 8. In this figure, the numeral 40 represents any wellknown form of picture scanning mechanismby means of which the shade char In order to indicated schematically by the numeral 42. The

modulated audio frequency carrier current may the device! as already described. When the devices tll, 4!, 42 and 43 are set in operation, there is impressed upon the telephone subscribers loop 41 a modulated alternating carrier current oi audio frequencythe modulations corresponding 1 to the shade characteristics of the picture being transmitted, the subscribers loop 4? connects the subscribers telephone equipment with the telephone exchange. At the other end of the telephone line 49 vthe received currents pass through the local telephone exchange 5t and thence to the local subscribers loop 5i where they are reproduced by the telephone ear-piece 52. fore, setup a magnetic field having a carrier frequency determined by the source at which is modulated in accordance with the picture Ming transmitted. The ear-piece 52 is placed on top of a coupling unit i as already described whereby there is introduced into the conductors i2 2. similar current to that impressed upon the conductors i2 at the transmitter. ihe currents from conductors i2 at the receiver are then used to operate any wellknown form of picture scanning and reproducing mechanism designated generally by the numeral ML For a detailed description of typical transmitting and receiving The field magnets of the ear-piece 52 thereapparatus that may be used to convert the picture into currents and to reconvert the currents into a reproduced picture, reference may be had to Bell System Technical Journal, April 1925, pages -211. 1

It will be understood of course that while Fig. 9 discloses the coupling devices as used in a system equally well used in transmitting any other kind of signals. Furthermore, it is'not necessary that the signals be transmitted in the form of a modulated carrier wave although this is advisable when transmission is effected over normal telephone lines. In using the equipment of Fig. 9 to transmit a picture for example, the telephone user at the transmitting station removesthe earpiece 46 from its switch hook (not shown) and places a call in the usual way for the subscriber at the distant point where the picture is to be received. After the telephone connection has been established in the usual way through the exchanges 48 and 50, the called subscriber answers by removing the telephone ear-piece 52 from its switch hook (not shown) and rests it on the-coupling unit I. The transmitting and receiving picture mechanism is then set in opof transmitting picture signals that they can be eration and the picture can be transmitted and received without any physical contact with the telephone lines and without requiring any permanent fastening of the'ear-pieces 46 and 52 to the coupling units I.

It will be understood of course that the invention is notlimited to the use of the coupling device I with a particular type of ear-piece. For example, while Figs. 1, 2 and 9 show an ear-piece of the conventional desk-set type, it will be understood that the devices I can likewise be used with so-called hand sets of the French type,

it being necessary merely to place the hand set I.

on the table 45 so that the ear-piece of the set rests on the top of unit I.

Various changes and modifications may be made in the apparatus disclosed without departing-rrom the spirit and scope of the invention.

What I claim is: n

a 1. A device for electro-magnetically coupling a signal generator to the coils of a telephone earpiece comprising a magnetic core, a winding for said core to be energized by said generator, and

a housing for said core and coil, said housing .having means to receive and support said earpiece with the coils of the ear-piece in registry with the said core, said housing having at least one sound channel therethrough to the open air 3 through said base to the open air to allow sound waves to pass therethrough', and a rim on said base on which said ear-piece -is adapted to rest.

3. An arrangement according to claim 2 in which said base is provided with a plurality oi sound deadening pedestals for spacing the base from a table or other support;

4. An arrangement according to claim 2 in which said rim is provided with a layer of sound deadening material on which the rim 0! the earpiece rests.

'said housing, and a supporting base' to receive u said housing, said support base having a plurality of sound channels open to the air to allow sound waves to pass therethrough.

AUSTIN G. COOLEY. 

